Questions And Answers

If a person is grounded with a wrist strap and is wearing a smock with the smocks sleeve rolled up above their elbows and their bare arms are exposed with no garments exposed is there any risk of ESD damage to the ESDS assembly they are building?

Answer

Not from the bare skin of a grounded operator. With ESD sleeve rolled up, if no clothing is exposed, it is OK. It is important that the ESD smock be grounded and enclose all the worker’s clothing around their torso area.

Per ESD Handbook TR 20.20 paragraph 5.3.13.1 Introduction and Purpose/ General Information "While a person may be grounded using a wrist strap or other grounding methods, that does not mean that insulative clothing fabrics can dissipate a charge to that person's skin and then to ground. Clothing usually is electrically separate or isolated from the body."

ESD Handbook TR 20.20 paragraph 5.3.13.2.6 Proper Use

"After verifying that the garment has electrical conductivity through all panels, the garment should be electrically bonded to the grounding system of the wearer so as not to act as a floating [conductor]. Garments should be worn with the front properly snapped or buttoned to avoid exposure of possible charges on personal clothing worn under the garment."